Double-ended flexure bearing

ABSTRACT

A flexure bearing having a first sleeve and a second sleeve is provided. Each sleeve includes a first pillar having a first end attached to the sleeve and a second end projecting outwardly from the sleeve and a second pillar having a first end attached to the sleeve and a second end projecting outwardly from the sleeve parallel to and diametrically opposed to the first pillar. The flexure bearing has a plurality of blind holes and a plurality of compression springs, each compression spring having a first spring end fit into one of the blind holes of a pillar of the first sleeve and a second spring end fit into a corresponding blind hole of an adjacent pillar of the second sleeve when the second sleeve is interconnected to the first sleeve.

BACKGROUND Technical Field

The present disclosure is directed to bearings used for compliantmechanisms and, more particularly, relates to flexure bearings andmethods of assembling the flexure bearings.

Description of Related Art

The “background” description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent it is described in thisbackground section, as well as aspects of the description which may nototherwise qualify as prior art at the time of filing, are neitherexpressly or impliedly admitted as prior art against the presentinvention.

Bearings are generally used in various industrial applications tofacilitate rotational or linear movement between two components. Whensuch bearings are used for relative movements between two components,lubrication is applied in the bearings to ease operation thereof and tominimize wear in the moving components, which in turn increaseproductive life of the components. In some industrial applications,bearings may be used for facilitating movement between two or threeelements, however, there is a restriction or limitation to uselubricants for the bearings. In such kind of applications, flexurebearings are used to serve the same function as of the conventionalbearings to facilitate movement between the elements, however, theflexure bearings provide limited angle of rotation. Also, the flexurebearings eliminate the need of lubrication.

In the existing designs, the movement of the flexure bearings isachieved by deformation of blade flexures, which experience cyclicfatigue loads. Further, the angle of rotation achieved in the existingflexure bearing design is ±20 degrees. Conventional flexure bearingsexperience fatigue failure due to cyclic loads and thus the blade designmay not be a viable solution in an application that is exposed tovibration which may cause damage or lead to failure of the equipment.Also, acceptable corrosion rate of the existing design is limitedbecause of tight dimensional tolerance between the blades and housing ofthe flexure bearings. Hence, there remains a need to develop a flexurebearing that overcomes the aforementioned shortcomings of the existingflexure bearing design. Further, the existing designs suffer from one ormore drawbacks hindering their adoption.

Accordingly, it is one object of the present disclosure to provide aflexure bearing that has enhanced fatigue life and can be useful forapplication that is exposed to vibration.

SUMMARY

In an exemplary embodiment, a flexure bearing is described. The flexurebearing includes a first sleeve and a second sleeve. Each sleeveincludes a first pillar having three sides, and a first end of the firstpillar is attached to an inside wall of the sleeve, and a second end ofthe first pillar projects outwardly from the sleeve parallel to an axisof the sleeve. Each sleeve further includes a second pillar having threesides, and a first end of the second pillar is attached to the insidewall of the sleeve, and a second end of the second pillar projectsoutwardly from the sleeve such that the second pillar is parallel to anddiametrically opposed to the first pillar. The flexure bearing furtherincludes a plurality of blind holes, each blind hole near each of thefirst end and the second end of each pillar. The flexure bearing furtherincludes a plurality of compression springs, each compression springhaving a first spring end configured to fit into one of the blind holesof a pillar of the first sleeve and a second spring end configured tofit into a corresponding blind hole of an adjacent pillar of the secondsleeve when the second sleeve is interconnected to the first sleeve.

In another exemplary embodiment, a double-ended flexure bearing isdescribed. The double-ended flexure bearing includes a first outersleeve including a first pillar which projects outwardly from the firstouter sleeve in a first direction, a second outer sleeve including asecond pillar which projects outwardly from the second outer sleeve in asecond direction, and a central rotor ring having an axis concentricwith the first outer sleeve and the second outer sleeve. The centralrotor ring is configured to engage with and connect to the first outersleeve and the second outer sleeve along the axis. The central rotorring includes a third pillar which projects outwardly from the centralrotor ring in the first direction and in the second direction, a fourthpillar which projects outwardly from the central rotor ring in the firstdirection and in the second direction, and a plurality of blind holes ineach pillar. The double-ended flexure bearing further includes aplurality of compression springs configured to connect each of theplurality of blind holes of each pillar to a blind hole of an adjacentpillar, such that the first outer sleeve abuts a first edge of thecentral rotor ring and the second outer sleeve abuts a second edge ofthe central rotor ring.

In another exemplary embodiment, a method of assembling a flexurebearing is described. The method incudes inserting each first spring endof each compression spring of a plurality of compression springs into ablind hole of a pillar attached to a first sleeve, and inserting eachsecond spring end of each compression spring into a corresponding blindhole of an adjacent pillar attached to one of a second sleeve and acentral rotor ring.

The foregoing general description of the illustrative embodiments andthe following detailed description thereof are merely exemplary aspectsof the teachings of this disclosure, and are not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of this disclosure and many of theattendant advantages thereof will be readily obtained as the samebecomes better understood by reference to the following detaileddescription when considered in connection with the accompanyingdrawings, wherein:

FIG. 1 is a perspective view of a flexure bearing, according to certainembodiments.

FIG. 2A is a perspective view of a first sleeve of the flexure bearing,according to certain embodiments.

FIG. 2B is a cross-sectional view taken along a line A-A′ of the firstsleeve of FIG. 2A showing a first pillar thereof, according to certainembodiments.

FIG. 2C is a cross-sectional view taken along the line A-A′ of the firstsleeve of FIG. 2A showing a second pillar thereof, according to certainembodiments.

FIG. 3A is a perspective view of a second sleeve of the flexure bearing,according to certain embodiments.

FIG. 3B is a cross-sectional view taken along a line B-B′ of the secondsleeve of FIG. 3A showing a first pillar thereof, according to certainembodiments.

FIG. 3C is a cross-sectional view taken along the line B-B′ of thesecond sleeve of FIG. 3A showing a second pillar thereof, according tocertain embodiments.

FIG. 4 is an exploded view of the flexure bearing, according to certainembodiments.

FIG. 5A is a front view of the flexure bearing of FIG. 1 , according tocertain embodiments.

FIG. 5B is a rear view of the flexure bearing of FIG. 1 , according tocertain embodiments.

FIG. 6 is a perspective view of a double-ended flexure bearing,according to certain embodiments.

FIG. 7A is a perspective view of a first outer sleeve of thedouble-ended flexure bearing of FIG. 6 , according to certainembodiments.

FIG. 7B is a cross-sectional view taken along a line C-C′ of the firstouter sleeve of FIG. 7A showing a first pillar thereof, according tocertain embodiments.

FIG. 8A is a perspective view of a second outer sleeve of thedouble-ended flexure bearing of FIG. 6 , according to certainembodiments.

FIG. 8B is a cross-sectional view taken along a line D-D′ of the secondouter sleeve of FIG. 8A showing a second pillar thereof, according tocertain embodiments.

FIG. 9A is a perspective view of a central rotor ring of thedouble-ended flexure bearing of FIG. 6 , according to certainembodiments.

FIG. 9B is a cross-sectional view taken along a line E-E′ of the centralrotor ring of FIG. 9A showing a third pillar thereof, according tocertain embodiments.

FIG. 9C is a cross-sectional view taken along the line E-E′ of thecentral rotor ring of FIG. 9A showing a fourth pillar thereof, accordingto certain embodiments.

FIG. 10 is an exploded view of the double-ended flexure bearing,according to certain embodiments.

FIG. 11 is an exemplary illustration of implementation of the flexurebearing of FIG. 1 in an industrial application, according to certainembodiments.

FIG. 12 is an exemplary flowchart of a method of assembling the flexurebearing of FIG. 1 and the double-ended flexure bearing of FIG. 6 ,according to certain embodiments.

DETAILED DESCRIPTION

In the drawings, like reference numerals designate identical orcorresponding parts throughout the several views. Further, as usedherein, the words “a,” “an” and the like generally carry a meaning of“one or more,” unless stated otherwise.

Furthermore, the terms “approximately,” “approximate,” “about,” andsimilar terms generally refer to ranges that include the identifiedvalue within a margin of 20%, 10%, or preferably 5%, and any valuestherebetween.

The word compliant as used in the present disclosure is defined asflexible, i.e., able to bend.

In a non-limiting example, a compliant mechanism may be a robotic joint.In another non-limiting example, a compliant mechanism may be any one ofa strut joint, a tie rod joint, a steering shaft joint, and the like.

Aspects of this disclosure are directed to a single-ended flexurebearing and a double-ended flexure bearing for compliant mechanisms usedin industrial applications and methods of assembling the flexurebearings. The flexure bearing includes two or three sleeves each havingone or more pillars connected through multiple compression springs. Eachcompression spring is disposed between two adjacent pillars and mountedon blind holes provided in opposing side surfaces of the adjacentpillars. The compression springs are positioned between the adjacentpillars in compression state such that they are firmly mounted withinthe flexure bearing.

The bearing of the present disclosure may be used in applications suchas precision measuring equipment, a spacecraft thruster, an antenna, insolar array systems, as a haptic pantograph mechanism, an antennapointing mechanism, scanning space mechanisms, and the like.

Referring to FIG. 1 , a perspective view of a flexure bearing 100 isillustrated. The flexure bearing 100 includes a first sleeve 110 and asecond sleeve 120 coupled to each other with a plurality of compressionsprings 130. The first sleeve 110 includes a first circular body 112having a first pillar 114 and a second pillar 116 attached thereto andthe second sleeve 120 includes a second circular body 122 having a firstpillar 124, which is otherwise referred to as ‘the third pillar 124’,and a second pillar 126, which is otherwise referred to as ‘the fourthpillar 126’, attached thereto. The first sleeve 110 and the secondsleeve 120 are collectively referred to as ‘the sleeves 140’ andindividually referred to as ‘the sleeve 140’ unless otherwisespecifically mentioned. In particular, the first pillar 114 and thesecond pillar 116 of the first sleeve 110 are attached to the firstcircular body 112 such that they are diametrically opposite to eachother. Further, the first pillar 114 and the second pillar 116 of thefirst sleeve 110 are integrally formed with the first circular body 112.Alternatively, the first pillar 114 and the second pillar 116 may beindividual components and separately attached to the first circular body112. Similarly, the third pillar 124 and the fourth pillar 126 of thesecond sleeve 120 are attached to the second circular body 122 such thatthey are diametrically opposite to each other. Further, the third pillar124 and the fourth pillar 126 are integrally formed with the secondcircular body 122.

Alternatively, the third pillar 124 and the fourth pillar 126 may beindividual components and separately attached to the second circularbody 122. The first pillar 114, the second pillar 116, the third pillar124 and the fourth pillar 126 are collectively referred to as ‘thepillars 148’ and individually referred to as ‘the pillar 148’ unlessotherwise specifically mentioned. In a nonlimiting example, constructionand dimensional specifications of the first sleeve 110 and the secondsleeve 120 are identical and they are positioned 90 degrees apart withrespect to a central axis ‘L’ of the flexure bearing 100 to couple eachother with the help of the plurality of compression springs 130. Theflexure bearing 100 further includes a plurality of blind holes 150defined in the first pillar 114, the second pillar 116, the third pillar124 and the fourth pillar 126 to engage with the plurality ofcompression springs 130. The first sleeve 110 and the second sleeve 120are coupled in such a way that a gap 160 is defined therebetween toprovide rotational movement to the first sleeve 110 and the secondsleeve 120 with respect to each other.

Referring to FIG. 2A, a perspective view of the first sleeve 110 isillustrated. The first sleeve 110 includes the first circular body 112having a wall 202 defining an outer surface 204 and an inner surface206. The first circular body 112 has an outer diameter defined by theouter surface 204 of the wall 202. In an example, the outer diameter ofthe first circular body 112 may be 110 millimeters (mm). The wall 202has a thickness defined radially between the outer surface 204 and theinner surface 206 thereof. In an example, the thickness of the wall 202may be 7 mm. Further, the first circular body 112 has a width definedlongitudinally between a first edge 208 and a second edge 210 thereof.In an example, the width of the first circular body 112 may be 54 mm.The first pillar 114 is an elongated body having a length equal to orless than twice the width of the first circular body 112. The firstpillar 114 includes three sides such as a first side 212, a second side214, and a third side 216. Further, the first pillar 114 includes afirst end 218 attached to an inside wall, otherwise referred to as theinner surface 206 of the wall 202, of the first sleeve 110 and a secondend 220 projects outwardly from the first sleeve 110 parallel to an axis‘L1’ of the first sleeve 110.

Referring to FIG. 2B, a cross-sectional view taken along a line A-A′ ofthe first sleeve 110 is illustrated to show the first pillar 114.Referring to FIGS. 2A-2B, the first side 212 of the first pillar 114 isshaped to confirm to a sector of an inner surface of the sleeve 140,particularly, the inner surface 206 of the wall 202 of the firstcircular body 112 of the first sleeve 110. The first side 212 of thefirst pillar 114 has a curved surface 212S defined by a radius ofcurvature equal to a radius of curvature of the inner surface 206 of thewall 202 of the first circular body 112. The second side 214 of thefirst pillar 114 has a first flat surface 214S and the third side 216 ofthe first pillar 114 has a second flat surface 216S perpendicular to anedge of the first flat surface 214S. The curved surface 212S, the firstflat surface 214S and the second flat surface 216S together define anouter surface of the first pillar 114.

As shown in FIG. 2B, the first pillar 114 has a first blind hole 222Anear a first end 218A of the second side 214, a second blind hole 222Bnear a first end 218B of the third side 216, a third blind hole 222Cnear a second end 220A of the second side 214, and a fourth blind hole222D near a second end 220B of the third side 216. Particularly, thefirst blind hole 222A and the third blind hole 222C are defined in thefirst flat surface 214S, and the second blind hole 222B and the fourthblind hole 222D are defined in the second flat surface 216S. The firstblind hole 222A, the second blind hole 222B, the third blind hole 222C,and the fourth blind hole 222D are collectively referred to as ‘theblind holes 150’ and individually referred to as ‘the blind hole 150’unless otherwise specifically mentioned. Each blind hole 150 has acircular cross section and has a diameter. In an example, the diameterof each blind hole 150 may be 14 mm.

The first end 218A of the second side 214 and the first end 218B of thethird side 216 are collectively or individually referred to as ‘thefirst end(s) 218’ of the first pillar 114 and the second end 220A of thesecond side 214 and the second end 220B of the third side 216 arecollectively or individually referred to as ‘the second end(s) 220’ ofthe first pillar 114 unless otherwise specifically mentioned. Each ofthe first blind hole 222A and the second blind hole 222B is defined atan offset distance from an edge of the first end 218A of the second side214 and an edge from the first end 218B of the third side 216,respectively. Similarly, each of the third blind hole 222C and thefourth blind hole 222D is defined at an offset distance from an edge ofthe second end 220A of the second side 214 and an edge from the secondend 220B of the third side 216, respectively. The offset distance may bedefined as a distance between the edge of the first end 218 of the firstpillar 114 and a center of the blind hole 150. In an example, the offsetdistance may be 20 mm. Referring to FIG. 2C, a cross-sectional viewtaken along the line A-A′ of the first sleeve 110 is illustrated to showthe second pillar 116. Referring to FIGS. 2A and 2C, the second pillar116 is an elongated body having a length equal to the length of thefirst pillar 114 and includes three sides such as a first side 232, asecond side 234, and a third side 236. Further, the second pillar 116includes a first end 238 attached to the inside wall, otherwise referredto as the inner surface 206 of the wall 202, of the first sleeve 110diametrically opposite to the first pillar 114 and a second end 240projects outwardly from the first sleeve 110 parallel to the axis ‘L1’and the first pillar 114 of the first sleeve 110. The first side 232 ofthe second pillar 116 is shaped to confirm to a sector of the innersurface of the sleeve 140, particularly, the inner surface 206 of thewall 202 of the first circular body 112. The first side 232 of thesecond pillar 116 has a curved surface 232S defined by a radius ofcurvature equal to the radius of curvature of the inner surface 206 ofthe wall 202 of the first circular body 112. The second side 234 of thesecond pillar 116 has a first flat surface 234S and the third side 236of the second pillar 116 has a second flat surface 236S perpendicular toan edge of the first flat surface 234S. The curved surface 232S, thefirst flat surface 234S and the second flat surface 236S together definean outer surface of the second pillar 116.

As shown in FIG. 2C, the second pillar 116 has a first blind hole 242Anear a first end 238A of the second side 234, a second blind hole 242Bnear a first end 238B of the third side 236, a third blind hole 242Cnear a second end 240A of the second side 234, and a fourth blind hole242D near a second end 240B of the third side 236. Particularly, thefirst blind hole 242A and the third blind hole 242C are defined in thefirst flat surface 234S, and the second blind hole 242B and the fourthblind hole 242D are defined in the second flat surface 236S of thesecond pillar 116. The first blind hole 242A, the second blind hole242B, the third blind hole 242C, and the fourth blind hole 242D arecollectively referred to as ‘the blind holes 150’ and individuallyreferred to as ‘the blind hole 150’ unless otherwise specificallymentioned. The first end 238A of the second side 234 and the first end238B of the third side 236 are collectively or individually referred toas ‘the first end 238’ of the second pillar 116 and the second end 240Aof the second side 234 and the second end 240B of the third side 236 arecollectively or individually referred to as ‘the second side 240’ of thesecond pillar 116 unless otherwise specifically mentioned. Thedimensional specifications of the blind holes 150 and the offsetdistance of the second pillar 116 are identical to that of the firstpillar 114.

Referring to FIG. 3A, a perspective view of the second sleeve 120 isillustrated. The second sleeve 120 includes the second circular body 122having a wall 302 defining an outer surface 304 and an inner surface306. The second circular body 122 has an outer diameter defined by theouter surface 304, a thickness defined radially between the outersurface 304 and the inner surface 306, and a width definedlongitudinally between a first edge 308 and a second edge 310, which areequal to that of the first circular body 112. The third pillar 124 is anelongated body having a length equal to or less than twice the width ofthe second circular body 122 and includes three sides such as a firstside 312, a second side 314, and a third side 316. Further, the thirdpillar 124 includes a first end 318 attached to an inside wall,otherwise referred to as the inner surface 306 of the wall 302, of thesecond sleeve 120 and a second end 320 projects outwardly from thesecond sleeve 120 parallel to an axis ‘L2’ of the second sleeve 120.

Referring to FIG. 3B, a cross-sectional view taken along a line B-B′ ofthe second sleeve 120 is illustrated to show the third pillar 124.Referring to FIGS. 3A-3B, the first side 312 of the third pillar 124 isshaped to confirm to a sector of an inner surface of the sleeve 140, orthe inner surface 306 of the wall 302 of the second circular body 122.Particularly, the first side 312 of the third pillar 124 has a curvedsurface 312S defined by a radius of curvature equal to a radius ofcurvature of the inner surface 306 of the wall 302 of the secondcircular body 122. The second side 314 of the third pillar 124 has afirst flat surface 314S and the third side 316 of the third pillar 124has a second flat surface 316S perpendicular to an edge of the firstflat surface 314S. The curved surface 312S, the first flat surface 314Sand the second flat surface 316S together define an outer surface of thethird pillar 124.

As shown in FIG. 3B, the third pillar 124 has a first blind hole 322Anear a first end 318A of the second side 314, a second blind hole 322Bnear a first end 318B of the third side 316, a third blind hole 322Cnear a second end 320A of the second side 314, and a fourth blind hole322D near a second end 320B of the third side 316. Particularly, thefirst blind hole 322A and the third blind hole 322C are defined in thefirst flat surface 314S, and the second blind hole 322B and the fourthblind hole 322D are defined in the second flat surface 316S. The firstblind hole 322A, the second blind hole 322B, the third blind hole 322C,and the fourth blind hole 322D are collectively referred to as ‘theblind holes 150’ and individually referred to as ‘the blind hole 150’unless otherwise specifically mentioned. The first end 318A of thesecond side 314 and the first end 318B of the third side 316 arecollectively referred to as ‘the first end(s) 318’ of the third pillar124 and the second end 320A of the second side 314 and the second end320B of the third side 316 are collectively referred to as ‘the secondend(s) 320’ of the third pillar 124 unless otherwise specificallymentioned.

Referring to FIG. 3C, a cross-sectional view taken along the line B-B′of the second sleeve 120 is illustrated to show the fourth pillar 126.Referring to FIGS. 3A and 3C, the fourth pillar 126 is an elongated bodyhaving a length equal to the length of the third pillar 124 and includesthree sides such as a first side 332, a second side 334, and a thirdside 336. Further, the fourth pillar 126 includes a first end 338attached to the inside wall, otherwise referred to as the inner surface306 of the wall 302, of the second sleeve 120 diametrically opposite tothe third pillar 124 and a second end 340 projects outwardly from thesecond sleeve 120 parallel to the axis ‘L2’ and the third pillar 124 ofthe second sleeve 120. The first side 332 of the fourth pillar 126 isshaped to confirm to a sector of the inner surface of the sleeve 140, orthe inner surface 306 of the wall 302 of the second circular body 122.Particularly, the first side 332 of the second pillar 126 has a curvedsurface 332S defined by a radius of curvature equal to the radius ofcurvature of the inner surface 306 of the wall 302 of the secondcircular body 122. The second side 334 of the fourth pillar 126 has afirst flat surface 334S and the third side 336 of the fourth pillar 126has a second flat surface 336S perpendicular to an edge of the firstflat surface 334S. The curved surface 332S, the first flat surface 334Sand the second flat surface 336S together define an outer surface of thefourth pillar 126.

As shown in FIG. 3C, the fourth pillar 126 has a first blind hole 342Anear a first end 338A of the second side 334, a second blind hole 342Bnear a first end 338B of the third side 336, a third blind hole 342Cnear a second end 340A of the second side 334, and a fourth blind hole342D near a second end 340B of the third side 336. Particularly, thefirst blind hole 342A and the third blind hole 342C are defined in thefirst flat surface 334S, and the second blind hole 342B and the fourthblind hole 342D are defined in the second flat surface 336S. The firstblind hole 342A, the second blind hole 342B, the third blind hole 342C,and the fourth blind hole 342D are collectively referred to as ‘theblind holes 150’ and individually referred to as ‘the blind hole 150’unless otherwise specifically mentioned. The first end 338A of thesecond side 334 and the first end 338B of the third side 336 arecollectively referred to as ‘the first end(s) 338’ of the fourth pillar126 and the second end 340A of the second side 334 and the second end340B of the third side 336 are collectively referred to as ‘the secondend(s) 340’ of the fourth pillar 126 unless otherwise specificallymentioned.

Referring to FIG. 4 , an exploded view of the flexure bearing 100 isillustrated. The flexure bearing 100 includes a plurality of end caps402 configured to engage with the plurality of blind holes 150. Theplurality of end caps 402 includes a first cap 402 ₁, a second cap 402₂, a third cap 402 ₃, and a fourth cap 402 ₄ configured to engage withthe first blind hole 222A, the second blind hole 222B, the third blindhole 222C, and the fourth blind hole 222D, respectively, of the firstpillar 114 of the first sleeve 110. The plurality of end caps 420further includes a fifth cap 402 ₅, a sixth cap 402 ₆, a seventh cap 402₇, and an eight cap 402 ₈ configured to engage with the first blind hole242A, the second blind hole 242B, the third blind hole 242C, and thefourth blind hole 242D, respectively, of the second pillar 116 of thefirst sleeve 110. The plurality of end caps 402 further includes anineth cap 402 ₉, a tenth cap 402 ₁₀, an eleventh cap 402 ₁₁, and atwelfth cap 402 ₁₂ configured to engage with the first blind hole 322A,the second blind hole 322B, the third blind hole 322C, and the fourthblind hole 322D, respectively, of the third pillar 124 of the secondsleeve 120. The plurality of end caps 402 further includes a thirteenthcap 402 ₁₃, a fourteenth cap 402 ₁₄, a fifteenth cap 402 ₁₅, and asixteenth cap 402 ₁₆ configured to engage with the first blind hole342A, the second blind hole 342B, the third blind hole 342C, and thefourth blind hole 342D, respectively, of the fourth pillar 126 of thesecond sleeve 120. The plurality of end caps 402 may be individuallyreferred to as ‘the end cap 402’ unless otherwise specificallymentioned.

The end cap 402 is a hollow cylindrical body having a diameter,otherwise referred to as the outer diameter, equal to the diameter ofthe blind hole 150 such that the end cap 402 is slidably received withinthe blind hole 150. Further, the end cap 402 has a length equal to adepth of the blind hole 150 such that the end cap 402 is received withinthe blind hole 150 without leaving any portion thereof projected outsidethe blind hole 150. The end cap 402 is further configured to engage withan end of each of the compression springs 130. Particularly, the end cap402 has an inner diameter greater than or equal to an outer diameter ofthe compression spring 130 such that the end of the compression spring130 is slidably received within the end cap 402. During an assembly ofthe flexure bearing 100, in one example, the end cap 402 may be firmlyengaged within the blind hole 150 such that the sleeve 140 and the blindhole 150 may be formed as one component. In another example, the end cap402 may be attached to the ends of the compression spring 130 such thatthe compression spring 130 and the end caps 402 together may be formedas one component. The plurality of compression springs 130 includes afirst compression spring 404 ₁ having a first spring end 404 _(1a) and asecond spring end 404 _(1b), a second compression spring 404 ₂ having afirst spring end 404 _(2a) and a second spring end 404 _(2b), a thirdcompression spring 404 ₃ having a first spring end 404 _(3a) and asecond spring end 404 _(3b), a fourth compression spring 404 ₄ having afirst spring end 404 _(4a) and a second spring end 404 _(4b), a fifthcompression spring 404 ₅ having a first spring end 404 _(5a) and asecond spring end 404 _(5b), a sixth compression spring 404 ₆ having afirst spring end 404 _(6a) and a second spring end 404 _(6b), a seventhcompression spring 404 ₇ having a first spring end 404 _(7a) and asecond spring end 404 _(m), and an eighth compression spring 404 ₈having a first spring end 404 _(8a) and a second spring end 404 _(8b)configured to rotatably couple the first sleeve 110 with the secondsleeve 120. Each compression spring 130 has the first spring endconfigured to fit into one of the blind holes 150 of the pillar 148 ofthe first sleeve 110 and the second spring end configured to fit into acorresponding blind hole 150 of an adjacent pillar 150 of the secondsleeve 120 when the second sleeve 120 is interconnected to the firstsleeve 110. The plurality of compression springs 130 is individuallyreferred to as ‘the compression spring 130’ unless otherwisespecifically mentioned. The compression spring 130 is alternativelyreferred to ‘the spring 130’ and, for example, the first compressionspring 404 ₁is alternatively referred to as ‘the first spring 404 ₁’.The compression spring 130 is a helical compression spring. Thecompression spring 130 has a length at least three times of the depth ofthe blind hole 150. Each compression spring 130 includes a first springend configured to engage with an end cap 402, otherwise referred to as‘the first end cap 402’, and a second spring end configured to engagewith an end cap 402, otherwise referred to as ‘the second end cap 402’.

Referring to FIGS. 5A and 5B, a front view and a rear view,respectively, of the flexure bearing 100 of FIG. 1 are illustrated.Referring to FIGS. 1 through 5B, during an assembly of the flexurebearing 100, the first sleeve 110 and the second sleeve 120 are alignedat an offset angle of 90 degrees with respect to the central axis ‘L’ ofthe flexure bearing 100. In a nonlimiting example, the first pillar 114and the second pillar 116 of the first sleeve 110 are aligned verticallyand the third pillar 124 and the fourth pillar 126 of the second sleeve120 are positioned horizontally such that the first and the secondsleeves 110, 120 are aligned at the offset angle of 90 degrees. Furter,the first pillar 114 and the second pillar 116 of the first sleeve 110are inserted between the third pillar 124 and the fourth pillar 126 ofthe second sleeve 120. The first sleeve 110 and the second sleeve 120are engaged in such a way that the gap 160 is defined between the secondedge 210 of the first sleeve 110 and the second edge 310 of the secondsleeve 120. In an example, the gap 160 between the first sleeve 110 andthe second sleeve 120 may be 2 mm. When the first sleeve 110 and thesecond sleeve 120 are assembled with the gap 160 therebetween, the blindholes 150 of the first pillar 114 and the second pillar 116 are alignedwith corresponding blind holes 150 of the third pillar 124 and thefourth pillar 126. Further, the first spring end of each compressionspring 130 is inserted into the blind holes 150 of the first and secondpillars 114, 116 of the first sleeve 110 and the second spring end ofeach compression spring 130 is inserted into the corresponding blindholes 150 of the third and fourth pillars 124, 126 of the second sleeve120. The end caps 402 may be inserted within the blind holes 150 of thesleeves 140 during the manufacturing thereof.

Referring to FIG. 6 , a perspective view of a double-ended flexurebearing 600 is illustrated. The double-ended flexure bearing 600includes a first outer sleeve 610, alternatively referred to as ‘thefirst sleeve 610’, and a second outer sleeve 620, alternatively referredto as ‘the second sleeve 620’ coupled to each other with a plurality ofcompression springs 630. The first outer sleeve 610 includes a firstcircular body 612 having a first pillar 614 attached thereto and thesecond outer sleeve 620 includes a second circular body 622 having asecond pillar 624 attached thereto. Further, the first pillar 614 of thefirst outer sleeve 610 and the second pillar 624 of the second outersleeve 620 are integrally formed with the first circular body 612 andthe second circular body 622, respectively. Alternatively, the firstpillar 614 and the second pillar 624 may be individual components andseparately attached to the first circular body 612 and the secondcircular body 622, respectively. The first outer sleeve 610 and thesecond outer sleeve 620 are collectively referred to as ‘the sleeves640’ and individually referred to as ‘the sleeve 640’ unless otherwisespecifically mentioned. In a nonlimiting example, construction anddimensional specifications of the first outer sleeve 610 and the secondouter sleeve 620 are identical and they are positioned 180 degrees apartwith respect to a central axis ‘LA’ of the double-ended flexure bearing600 to couple each other with the help of the plurality of compressionsprings 630.

The double-ended flexure bearing 600 further includes a central rotorring 642 configured to engage with and connect to the first outer sleeve610 and the second outer sleeve 620. The central rotor ring 642 includesa third pillar 644 and a fourth pillar 646 configured to engage with thefirst pillar 614 of the first outer sleeve 610 and the second pillar 624of the second outer sleeve 620 using the plurality of compressionsprings 630. Particularly, the central rotor ring 642 is disposedbetween the first outer sleeve 610 and the second outer sleeve 620 andcoaxially aligned with the first outer sleeve 610 and the second outersleeve 620 to engage therewith using the plurality of compressionsprings 630. The first pillar 614, the second pillar 624, the thirdpillar 644, and the fourth pillar 646 are collectively referred to as‘the pillars 648’ and individually referred to as ‘the pillar 648’unless otherwise specifically mentioned. Each of the first pillar 614,the second pillar 624, the third pillar 644 and the fourth pillar 646includes a plurality of blind holes 650, which is individually referredto as ‘the blind hole 650’. The plurality of compression springs 630 isconfigured to connect each of the plurality of blind holes 650 of eachpillar 648 to a blind hole 650 of an adjacent pillar 648, such that thefirst outer sleeve 610 abuts a first edge 652 of the central rotor ring642 and the second outer sleeve 620 abuts a second edge 654 of thecentral rotor ring 642. The first outer sleeve 610, the second outersleeve 620, and the central rotor ring 642 are coupled in such a waythat a first gap 660A is defined between the first outer sleeve 610 andthe central rotor ring 642 and a second gap 660B is defined between thesecond outer sleeve 620 and the central rotor ring 642 to providerotational movement with respect to each other.

Referring to FIG. 7A, a perspective view of the first outer sleeve 610is illustrated. The first outer sleeve 610 includes the first circularbody 612 having a wall 702 defining an outer surface 704 and an innersurface 706. The first circular body 612 has an outer diameter definedby the outer surface 704 of the wall 702, a thickness defined radiallybetween the outer surface 704 and the inner surface 706, and a widthdefined longitudinally between a first edge 708 and a second edge 710.The first pillar 614 is an elongated body that projects outwardly fromthe first outer sleeve 610 in a first direction ‘D1’ and has a lengthequal to or less than thrice the width of the first circular body 612.The first pillar 614 includes three sides such as a first side 712, asecond side 714, and a third side 716. Further, the first pillar 614includes a first end 718 attached to a first inside wall, otherwisereferred to as the inner surface 706 of the wall 702, of the first outersleeve 610 and a second end 720 projects outwardly from the first outersleeve 610 parallel to an axis ‘LA1’ of the first outer sleeve 610.Particularly, a first end 718C of the first side 712 of the first pillar614 is attached to the first inside wall of the first outer sleeve 610.

Referring to FIG. 7B, a cross-sectional view taken along a line C-C′ ofthe first outer sleeve 610 is illustrated to show the first pillar 614.Referring to FIGS. 7A-7B, the first side 712 of the first pillar 614 isshaped to confirm to the first inside wall of the first outer sleeve610. Particularly, the first side 712 of the first pillar 614 is shapedto confirm to a first sector of an inner surface, which is otherwisereferred to as the inner surface 706 of the wall 702 of the firstcircular body 612, of the first outer sleeve 610. The first side 712 ofthe first pillar 614 has a curved surface 712S defined by a radius ofcurvature equal to a radius of curvature of the inner surface 706 of thewall 702 of the first circular body 612. The second side 714 of thefirst pillar 614 has a first flat surface 714S and the third side 716 ofthe first pillar 614 has a second flat surface 716S perpendicular to anedge of the first flat surface 714S. The curved surface 712S, the firstflat surface 714S and the second flat surface 716S together define anouter surface of the first pillar 614.

As shown in FIG. 7B, the first pillar 614 has a first blind hole 722Anear a first end 718A of the second side 714, a second blind hole 722Bnear a first end 718B of the third side 716, a third blind hole 722Cnear a second end 720A of the second side 714, and a fourth blind hole722D near a second end 720B of the third side 716, a fifth blind hole722E at a center 714C of the second side 714 and a sixth blind hole 722Fat a center 716C of the third side 716. Particularly, the first blindhole 722A, the third blind hole 722C and the fifth blind hole 722E aredefined in the first flat surface 714S, and the second blind hole 722B,the fourth blind hole 722D and the sixth blind hole 722F are defined inthe second flat surface 716S. The first blind hole 722A, the secondblind hole 722B, the third blind hole 722C, the fourth blind hole 722D,the fifth blind hole 722E and the sixth blind hole 722F are collectivelyreferred to as ‘the blind holes 650’ and individually referred to as‘the blind hole 650’ unless otherwise specifically mentioned. The firstend 718A of the second side 714, the first end 718B of the third side716 and the first end 718C of the first side 712 are collectively orindividually referred to as ‘the first end(s) 718’ of the first pillar614 and the second end 720A of the second side 714 and the second end720B of the third side 716 are collectively or individually referred toas ‘the second end(s) 720’ of the first pillar 614 unless otherwisespecifically mentioned.

Referring to FIG. 8A, a perspective view of the second outer sleeve 620is illustrated. The second outer sleeve 620 includes the second circularbody 622 having a wall 802 defining an outer surface 804 and an innersurface 806. The second circular body 622 has an outer diameter definedby the outer surface 804 of the wall 802, a thickness defined radiallybetween the outer surface 804 and the inner surface 806, and a widthdefined longitudinally between a first edge 808 and a second edge 810.The second pillar 624 is an elongated body that projects outwardly fromthe second outer sleeve 620 in a second direction ‘D2’ and has a lengthequal to or less than thrice the width of the second circular body 622.The second pillar 624 includes three sides such as a first side 812, asecond side 814, and a third side 816. Further, the second pillar 624includes a first end 818 attached to a second inside wall, otherwisereferred to as the inner surface 806 of the wall 802, of the secondouter sleeve 620 and a second end 820 projects outwardly from the secondouter sleeve 620 parallel to an axis ‘LA2’ of the second outer sleeve620. Particularly, a first end 818C of the first side 812 of the secondpillar 624 is attached to the second inside wall of the second outersleeve 620. Referring to FIG. 8B, a cross-sectional view taken along aline D-D′ of the second outer sleeve 620 is illustrated to show thesecond pillar 624. Referring to FIGS. 8A-8B, the first side 812 of thesecond pillar 624 is shaped to confirm to the second inside wall of thesecond outer sleeve 620. Particularly, the first side 812 of the secondpillar 624 is shaped to confirm to a second sector of an inner surface,which is otherwise referred to as the inner surface 806 of the wall 802of the second circular body 622, of the second outer sleeve 620. Thefirst side 812 of the second pillar 624 has a curved surface 812Sdefined by a radius of curvature equal to a radius of curvature of theinner surface 806 of the wall 802 of the second circular body 622. Thesecond side 814 of the second pillar 624 has a third flat surface 814S,alternatively referred to as ‘the first flat surface 814S’ and the thirdside 816 of the second pillar 624 has a fourth flat surface 816S,alternatively referred to as ‘the second flat surface 816S’,perpendicular to an edge of the third flat surface 814S. The curvedsurface 812S, the third flat surface 814S and the fourth flat surface816S together define an outer surface of the second pillar 624. As shownin FIG. 8B, the second pillar 624 has a first blind hole 822A near afirst end 818A of the second side 814, a second blind hole 822B near afirst end 818B of the third side 816, a third blind hole 822C near asecond end 820A of the second side 814, and a fourth blind hole 822Dnear a second end 820B of the third side 816, a fifth blind hole 822E ata center 814C of the second side 814 and a sixth blind hole 822F at acenter 816C of the third side 816. Particularly, the first blind hole822A, the third blind hole 822C and the fifth blind hole 822E aredefined in the third flat surface 814S, and the second blind hole 822B,the fourth blind hole 822D and the sixth blind hole 822F are defined inthe fourth flat surface 816S. The first blind hole 822A, the secondblind hole 822B, the third blind hole 822C, the fourth blind hole 822D,the fifth blind hole 822E and the sixth blind hole 822F are collectivelyreferred to as ‘the blind holes 650’ and individually referred to as‘the blind hole 650’ unless otherwise specifically mentioned.

The first end 818A of the second side 814, the first end 818B of thethird side 816 and the first end 818C for the first side 812 arecollectively or individually referred to as ‘the first end(s) 818’ ofthe second pillar 624 and the second end 820A of the second side 814 andthe second end 820B of the third side 816 are collectively orindividually referred to as ‘the second end(s) 820’ of the second pillar624 unless otherwise specifically mentioned.

Referring to FIG. 9A, a perspective view of the central rotor ring 642is illustrated. The central rotor ring 642 includes a third circularbody 901 having a wall 902 defining an outer surface 904 and an innersurface 906. The third circular body 901 has an outer diameter definedby the outer surface 904 of the wall 902, a thickness defined radiallybetween the outer surface 904 and the inner surface 906 and a widthdefined longitudinally between the first edge 652 and the second edge654. The central rotor ring 642 has an axis ‘LA3’ concentric with thefirst outer sleeve 610 and the second outer sleeve 620 at an assembledcondition of the double-ended flexure bearing 600. Particularly, theaxis ‘LA3’ of the central rotor ring 642 is coaxial with the axis ‘LA1’and the axis ‘LA2’ of the first outer sleeve 610 and the second outersleeve 620, respectively. The third pillar 644 is an elongated body thatprojects outwardly from the central rotor ring 642 in the firstdirection ‘D1’ and the in the second direction ‘D2’ and has a lengthequal to or less than thrice the width of the first outer sleeve 610 orthe second outer sleeve 620. The third pillar 644 includes three sidessuch as a first side 912, a second side 914 and a third side 916.Further, the third pillar 644 includes a first end 918 projectsoutwardly from the central rotor ring 642 in the second direction ‘D2’and a second end 920 projects outwardly from the central rotor ring 642in the first direction ‘D1’ parallel to the axis ‘LA3’ of the centralrotor ring 642. A center 912C of the first side 912 of the third pillar644 is attached to a first sector of a third inside wall, otherwisereferred to as the inner surface 906 of the wall 902, of the centralrotor ring 642.

Referring to FIG. 9B, a cross-sectional view taken along a line E-E′ ofthe central rotor ring 642 is illustrated to show the third pillar 644.Referring to FIGS. 9A-9B, the first side 912 of the third pillar 644 isshaped to confirm to a third sector of an inner surface, particularly,the inner surface 906 of the wall 902 of the third circular body 901, ofthe central rotor ring 642.

The first side 912 of the third pillar 644 has a curved surface 912Sdefined by a radius of curvature equal to a radius of curvature of theinner surface 906 of the wall 902 of the third circular body 901. Thesecond side 914 of the third pillar 644 has a fifth flat surface 914S,alternatively referred to as ‘the first flat surface 914S’, and thethird side 916 of the third pillar 644 has a sixth flat surface 916S,alternatively referred to as ‘the second flat surface 816S’,perpendicular to an edge of the fifth flat surface 914S. The curvedsurface 912S, the fifth flat surface 914S and the sixth flat surface916S together define an outer surface of the third pillar 644.

As shown in FIG. 9B, the third pillar 644 has a first blind hole 922Anear a first end 918A of the second side 914, a second blind hole 922Bnear a first end 918B of the third side 916, a third blind hole 922Cnear a second end 920A of the second side 914, and a fourth blind hole922D near a second end 920B of the third side 916, a fifth blind hole922E at a center 914C of the second side 914 and a sixth blind hole 922Fat a center 916C of the third side 916.

Particularly, the first blind hole 922A, the third blind hole 922C andthe fifth blind hole 922E are defined in the fifth flat surface 914S,and the second blind hole 922B, the fourth blind hole 922D and the sixthblind hole 922F are defined in the sixth flat surface 916S. The firstblind hole 922A, the second blind hole 922B, the third blind hole 922C,the fourth blind hole 922D, the fifth blind hole 922E and the sixthblind hole 922F are collectively referred to as ‘the blind holes 650’and individually referred to as ‘the blind hole 650’ unless otherwisespecifically mentioned. The first end 918A of the second side 914 andthe first end 918B of the third side 916 are collectively orindividually referred to as ‘the first end(s) 918’ of the third pillar644 and the second end 920A of the second side 914 and the second end920B of the third side 916 are collectively or individually referred toas ‘the second end(s) 920’ of the third pillar 644 unless otherwisespecifically mentioned.

Referring to FIG. 9C, a cross-sectional view taken along the line E-E′of the central rotor ring 642 is illustrated to show the fourth pillar646. Referring to FIGS. 9A and 9C, the fourth pillar 646 is an elongatedbody that projects outwardly from the central rotor ring 642 in thefirst direction ‘D1’ and the in the second direction ‘D2’ and has alength equal to or less than thrice the width of the first outer sleeve610 or the second outer sleeve 620. The fourth pillar 646 includes threesides such as a first side 932, a second side 934, and a third side 936.Further, the fourth pillar 646 includes a first end 938 projectsoutwardly from the central rotor ring 642 in the second direction ‘D2’and a second end 940 projects outwardly from the central rotor ring 642in the first direction ‘D1’ parallel to the axis ‘LA3’ of the centralrotor ring 642. A center 932C of the first side 932 of the fourth pillar646 is attached to a second sector of the third inside wall, otherwisereferred to as the inner surface 906 of the wall 902, of the centralrotor ring 642 diametrically opposite to the third pillar 644.Particularly, the first sector is diametrically opposed to the secondvector of the central rotor ring 642. The first side 932 of the fourthpillar 646 is shaped to confirm to the fourth sector of an inner surfaceof the central rotor ring 642, particularly, the inner surface 906 ofthe wall 902 of the third circular body 901. The first side 932 of thefourth pillar 646 has a curved surface 932S defined by a radius ofcurvature equal to the radius of curvature of the inner surface 906 ofthe wall 902 of the third circular body 901.

The second side 934 of the fourth pillar 646 has a seventh flat surface934S, alternatively referred to as ‘the first flat surface 934S’, andthe third side 936 of the fourth pillar 646 has an eighth flat surface936S, alternatively referred to as ‘the second flat surface 936S’,perpendicular to an edge of the seventh flat surface 934S. The curvedsurface 932S, the seventh flat surface 934S and the eighth flat surface936S together define an outer surface of the fourth pillar 646.

As shown in FIG. 9C, the fourth pillar 646 has a first blind hole 942Anear a first end 938A of the second side 934, a second blind hole 942Bnear a first end 938B of the third side 936, a third blind hole 942Cnear a second end 940A of the second side 934, and a fourth blind hole942D near a second end 940B of the third side 936, a fifth blind hole942E at a center 932C of the second side 934 and a sixth blind hole 942Fat a center 936C of the third side 936. Particularly, the first blindhole 942A, the third blind hole 942C and the fifth blind hole 942E aredefined in the seventh flat surface 934S, and the second blind hole942B, the fourth blind hole 942D and the sixth blind hole 942F aredefined in the eighth flat surface 936S. The first blind hole 942A, thesecond blind hole 942B, the third blind hole 942C, and the fourth blindhole 942D, the fifth blind hole 942E and the sixth blind hole 942F arecollectively referred to as ‘the blind holes 650’ and individuallyreferred to as ‘the blind hole 650’ unless otherwise specificallymentioned. The first end 938A of the second side 934 and the first end938B of the third side 936 are collectively or individually referred toas ‘the first end(s) 938’ of the fourth pillar 646 and the second end940A of the second side 934 and the second end 940B of the third side936 are collectively or individually referred to as ‘the second end(s)940’ of the third pillar 644 unless otherwise specifically mentioned.

Referring to FIG. 10 , an exploded view of the double-ended flexurebearing 600 is illustrated. The double-ended flexure bearing 600 mayinclude a plurality of end caps, identical to the end caps 402 of theflexure bearing 100, configured to attach with the plurality of blindholes 650 of the pillars 648 of the sleeves 640 and the central rotorring 642. During an assembly of the double-ended flexure bearing 600, inone example, the end caps may be firmly engaged within the blind holes650 such that the sleeves 640 and the blind holes 650 may be formed asone component. In another example, the end caps may be attached to theends of the compression springs 630 such that the compression springs630 and the end caps together may be formed as one component.

The plurality of compression springs 630 includes a first compressionspring 1004 ₁ having a first spring end 1004 _(1a) and a second springend 1004 _(1b), a second compression spring 1004 ₂ having a first springend 1004 _(2a) and a second spring end 1004 _(2b), a third compressionspring 1004 ₃ having a first spring end 1004 _(3a) and a second springend 1004 _(3b), a fourth compression spring 1004 ₄ having a first springend 1004 _(4a) and a second spring end 1004 _(4b), a fifth compressionspring 1004 ₅ having a first spring end 1004 _(5a) and a second springend 1004 _(5b), a sixth compression spring 1004 ₆ having a first springend 1004 _(6a) and a second spring end 1004 _(6b), a seventh compressionspring 1004 ₇ having a first spring end 1004 _(7a) and a second springend 1004 _(7b), an eighth compression spring 1004 ₈ having a firstspring end 1004 _(8a) and a second spring end 1004 _(8b), a ninethcompression spring 1004 ₉ having a first spring end 1004 _(9a) and asecond spring end 1004 _(9b), a tenth compression spring 1004 ₁₀ havinga first spring end 1004 _(10a) and a second spring end 1004 _(10b), aneleventh compression spring 1004 ₁₁ having a first spring end 1004_(11a) and a second spring end 1004 _(11b) and a twelfth compressionspring 1004 ₁₂ having a first spring end 1004 _(12a) and a second springend 1004 _(12b) configured to rotatably couple the first outer sleeve610 and the second outer sleeve 620 with the central rotor ring 642. Theplurality of compression springs 630 may be individually referred to as‘the compression spring 630’ unless otherwise specifically mentioned.The compression spring 630 may be alternatively referred to ‘the spring630’ and, for example, the first compression spring 1004 ₁ may bealternatively referred to as ‘the first spring 1004 ₁’ and so on. Thecompression spring 630 is a helical compression spring. Each compressionspring 630 has a first spring end configured to fit into one of theblind holes 650 of one of the pillars 648 and a second spring endconfigured to fit into a corresponding blind hole 650 of an adjacentpillar 648 when the first outer sleeve 610 and the second outer sleeve620 are interconnected with the central rotor ring 642.

Referring to FIG. 11 , an exemplary illustration of an implementation ofthe flexure bearing 100 of FIG. 1 in a mechanical system 1100 isillustrated. As shown in FIG. 11 , the flexure bearing 100 isimplemented in the mechanical system 1100 having a support leg 1102, abar 1104 horizontally attached to the support leg 1102 and an arm 1106movably coupled to the bar 1104. A linear actuator 1108 is coupled tothe bar 1104 and the arm 1106 to support movement of the arm 1106 withrespect to the bar 1104. The bar 1104 includes a first opening 1110configured to engage with the first sleeve 110 and the arm 1106 includesa second opening (not shown) configured to engage with the second sleeve120. Particularly, the first opening 1110 may have a diameter equal tothe diameter of the first circular body 112 of the first sleeve 110 andthe second opening may have a diameter equal to the diameter of thesecond circular body 122 of the second sleeve 120 as such the flexurebearing 100 may be engaged with the bar 1104 and the arm 1106 usingpress fit, interference fit, or any other mechanisms known in the art.When the linear actuator 1108 is actuated, the flexure bearing 100facilitates rotational movement of the arm 1106 relative to the bar 1104with respect to the central axis ‘L’ thereof. In the presentimplementation, a rotation angle achieved between the bar 1104 and thearm 1106 is 60 degrees, which is higher than the rotation angle ±20°achieved by the existing design. Particularly, the third pillar 124 andthe fourth pillar 126 of the second sleeve 120 rotate anticlockwisewhile the first pillar 114 and the second pillar 116 of the first sleeve110 remain stationary. As such, the first compression spring 404 ₁ andthe second compression spring 404 ₂ are compressed further and the fifthcompression spring 404 ₅ and the sixth compression spring 404 ₆ areexpanded. At the same time, the third compression spring 404 ₃ and thefourth compression spring 404 ₄ are compressed further and the seventhcompression spring 404 ₇ and the eighth compression spring 404 ₈ areexpanded.

The flexure bearing 100 of the present disclosure helps to achieve alarger rotation angle of ±30° compared to the rotation angle of ±20°achieved by the existing design. Further, the arrangement of thecompression springs 130 helps the flexure bearing 100 to mitigatefatigue failure which is otherwise caused due to the arrangements ofblades within the existing design, thereby the fatigue life of theflexure bearing 100 may be enhanced, especially, at high speedapplications. Additionally, the compression springs 130 facilitatereplacement and maintenance of the flexure bearing 100 more easily andmore economically. Further, the flexure bearing 100 helps to absorbvibrations with the help of the compression springs 130, which wouldotherwise be difficult with blades arrangement, and can be useful inapplications where vibrations cause damage or lead to failure ofequipment. Moreover, design of the flexure bearing 100 has a higheracceptable corrosion rate compared to the existing bearings as theacceptable corrosion rate of the existing bearings is very small becauseof the tight dimensional tolerance. The double-ended flexure bearing 600can be implemented in a mechanical system having three movable elements,in which two elements may be movable relative to a third element. Eachof the three elements may be attached to each of the first outer sleeve610, the second outer sleeve 620, and the central roto ring 642. Theaforementioned advantages may also be achieved with the double-endedflexure bearing 600.

The flexure bearing 100 and the double-ended flexure bearing 600 can beused in space applications (vacuum) as the requirement of lubrication iseliminated and food production equipment in the food industry as thereis no risk of lubrication leakage. Various applications including, butnot limited to, robotics and assembly line operations in the automobileindustry can bed benefited using the flexure bearing 100 and thedouble-ended flexure bearing 600 of the present disclosure. In anexample, the flexure bearing 100 or the double-ended flexure bearing 600can be used as a humanoid robot neck connecting body to head, and therobot wiring can be easily connected through a gap defined at the centerthereof.

Referring to FIG. 12 , a schematic flowchart of a method 1200 ofassembling the flexure bearing 100 and the double-ended flexure bearing600 is illustrated. Referring to FIGS. 1 to 5B, at step 1202, the method1200 includes inserting each first spring end of each compression spring130 of the plurality of compression springs 130 into the blind hole 150of the pillar 148 attached to the first sleeve 110. In particular, themethod 1200 includes inserting the first pillar 114 and the secondpillar 116 of the first sleeve 110 between the third pillar 124 and thefourth pillar 126 of the second sleeve 120. In one example, the end caps402 may be press fitted within the blind holes 150 of the pillars 148 ofthe sleeves 140 during manufacturing thereof. In an alternate example,the end caps 402 may be engaged with the blind holes 150 of the pillars148 of the sleeves 140 during the assembly of the flexure bearing 100.The method 1200 further includes abutting the first sleeve 110 againstthe second sleeve 120. The first sleeve 110 and the second sleeve 120are coupled in such a way that the gap 160 is defined therebetween.

At step 1204, the method 1200 includes inserting each second spring endof each compression spring 130 into the corresponding blind hole 150 ofthe adjacent pillar 148, such as the third pillar 124 and the fourthpillar 126, attached to the second sleeve 120. The method 1200 alsoincludes compressing each compression spring 130 before inserting eachsecond spring end of each compression spring 130 into the correspondingblind hole 150 of the adjacent pillar 148. The method 1200 of insertingeach first spring end and each second spring end of each of theplurality of compression springs 130 includes inserting the first springend 404 _(1a) of the first spring 404 ₁ into the first blind hole 222Aof the first end 218 of the first pillar 114 and inserting the secondspring end 404 _(1b) of the first spring 404 ₁ into the third blind hole342C of the second end 340 of the fourth pillar 126. The method 1200further includes inserting the first spring end 404 _(2a) of the secondspring 404 ₂ into the first blind hole 242A of the first end 238 of thesecond pillar 116 and inserting the second spring end 404 _(2b) of thesecond spring 404 ₂ into the fourth blind hole 322D of the second end320 of the third pillar 124. The method 1200 further includes insertingthe first spring end 404 _(3a) of the third spring 404 ₃ into the thirdblind hole 222C of the second end 220 of the first pillar 114 andinserting the second spring end 404 _(3b) of the third spring 404 ₃ intothe first blind hole 342A of the first end 338 of the fourth pillar 126.The method 1200 further includes inserting the first spring end 404_(4a) of the fourth spring 404 ₄ into the third blind hole 242C of thesecond end 240 of the second pillar 116 and inserting the second springend 404 _(4b) of the fourth spring 404 ₄ into the second blind hole 322Bof the first end 318 of the third pillar 124. The method 1200 furtherincludes inserting the first spring end 404 _(5a) of the fifth spring404 ₅ into the second blind hole 222B of the first end 218 of the firstpillar 114 and inserting the second spring end 404 _(5b) of the fifthspring 404 ₅ into the third blind hole 322C of the second end 320 of thethird pillar 124. The method 1200 further includes inserting the firstspring end 404 _(6a) of the sixth spring 404 ₆ into the second blindhole 242B of the first end 238 of the second pillar 116 and insertingthe second spring end 404 _(6b) of the sixth spring 404 ₆ into thefourth blind hole 342D of the second end 340 of the fourth pillar 126.The method 1200 further includes inserting the first spring end 404_(7a) of the seventh spring 404 ₇ into the fourth blind hole 222D of thesecond end 220 of the first pillar 114 and inserting the second springend 404 _(7b) of the seventh spring 404 ₇ into the first blind hole 322Aof the first end 318 of the third pillar 124.

The method 1200 further includes inserting the first spring end 404_(8a) of the eighth spring 404 ₈ into the fourth blind hole 242D of thesecond end 240 of the second pillar 116 and inserting the second springend 404 _(8b) of the eighth spring 404 ₈ into the second blind hole 342Bof the first end 338 of the fourth pillar 126.

Referring to FIG. 6 through FIG. 10 , at the step 1202, the method 1200includes inserting each first spring end of each compression spring 630of the plurality of compression springs 630 into the blind hole 650 ofthe pillar 648 attached to the first sleeve 610. In particular, themethod 1200 includes inserting the first pillar 614 of the first sleeve610 between the third pillar 644 and the fourth pillar 646 of thecentral rotor ring 642 until the first sleeve 610 abuts the first edge652 of the central rotor ring 642. The method 1200 further includesinserting the second pillar 624 of the second sleeve 620 between thethird pillar 644 and the fourth pillar 646 of the central rotor ring 642until the second sleeve 620 abuts the second edge 654 of the centralrotor ring 642.

Further, the method 1200 includes inserting the first spring end of eachof the plurality of compression springs 630 into one of the blind holes650.

At the step 1204, the method 1200 includes inserting each second springend of each compression spring 630 into the corresponding blind hole 650of the adjacent pillar 648 attached to one of the second sleeve 620 andthe central rotor ring 642. The method 1200 also includes compressingeach compression spring 630 before inserting each second spring end ofeach compression spring 630 into the corresponding blind hole 650 of theadjacent pillar 648. The method 1200 further includes inserting eachsecond spring end of each compression spring 630 of a first set of theplurality of compression springs 630 into a corresponding blind hole 650of an adjacent pillar 648 attached to one of the first sleeve 610 andthe second sleeve 620 and inserting each second spring end of eachcompression spring 630 of a second set of the plurality of compressionsprings 630 into a corresponding blind hole 650 of an adjacent pillar648 attached to the central rotor ring 642.

The method 1200 of inserting each first spring end and each secondspring end of the first set of the plurality of compression springs 630includes inserting the first spring end 1004 _(1a) of the first spring1004 ₁ into the first blind hole 722A near the first end 718 of thefirst pillar 614 and inserting the second spring end 1004 _(1b) of thefirst spring 1004 ₁ into the second blind hole 922B of the third pillar644. The method 1200 further includes inserting the first spring end1004 _(2a) of the second spring 1004 ₂ into the second blind hole 722Bnear the first end 718 of the first pillar 614 and inserting the secondspring end 1004 _(2b) of the second spring 1004 ₂ into the first blindhole 942A of the fourth pillar 646. The method 1200 further includesinserting the first spring end 1004 _(3a) of the third spring 1004 ₃into the third blind hole 722C near the second end 720 of the firstpillar 614 and inserting the second spring end 1004 _(3b) of the thirdspring 1004 ₃ into the fourth blind hole 922D near the second end 920 ofthe third pillar 644. The method 1200 further includes inserting thefirst spring end 1004 _(4a) of the fourth spring 1004 ₄ into the fourthblind hole 722D near the second end 720 of the first pillar 614 andinserting the second spring end 1004 _(4b) of the fourth spring 1004 ₄into the third blind hole 942C near the second end 940 of the fourthpillar 646. The method 1200 further includes inserting the first springend 1004 _(5a) of the fifth spring 1004 ₅ into the fifth blind hole 722Eat the center 714C of the second side 714 of the first pillar 614 andinserting the second spring end 1004 _(5b) of the fifth spring 1004 ₅into the sixth blind hole 922F at the center 916C of the third side 916of the third pillar 646. The method 1200 further includes inserting thefirst spring end 1004 _(6a) of the sixth spring 1004 ₆ into the sixthblind hole 722F at the center 716C of the third side 716 of the firstpillar 614 and inserting the second spring end 1004 _(6b) of the sixthspring 1004 ₆ into the fifth blind hole 942E at the center 934C of thesecond side 934 of the fourth pillar 646. The method 1200 furtherincludes inserting the first spring end 1004 _(7a) of the seventh spring1004 ₇ into the fifth blind hole 822E at the center 814C of the secondside 814 of the second pillar 624 and inserting the second spring end1004 _(7b) of the seventh spring 1004 ₇ into the fifth blind hole 922Eat the center 914C of the second side 914 of the third pillar 644. Themethod 1200 further includes inserting the first spring end 1004 _(8a)of the eighth spring 1004 ₈ into the sixth blind hole 822F at the center816C of the third side 816 of the second pillar 624 and inserting thesecond spring end 1004 _(8b) of the eighth spring 1004 ₈ into the sixthblind hole 942F at the center 936C of the third side 936 of the fourthpillar 646.

The method 1200 of inserting each first spring end and each secondspring end of the second set of the plurality of compression springs 630includes inserting the first spring end 1004 _(9a) of the nineth spring1004 ₉ into the third blind hole 822C of the second end 820 of thesecond pillar 624 and inserting the second spring end 1004 _(9b) of thenineth spring 1004 ₉ into the first blind hole 922A of the first end 918of the third pillar 646. The method 1200 further includes inserting thefirst spring end 1004 _(10a) of the tenth spring 1004 ₁₀ into the fourthblind hole 822D of the second end 820 of the second pillar 624 andinserting the second spring end 1004 _(10b) of the tenth spring 1004 ₁₀into the second blind hole 942B of the first end 938 of the fourthpillar 646. The method 1200 further includes inserting the first springend 1004 _(11a) of the eleventh spring 1004 ₁₁ into the first blind hole822A of the first end 818 of the second pillar 624 and inserting thesecond spring end 1004 _(11b) of the eleventh spring 1004 ₁₁ into thethird blind hole 922C of the second end 920 of the third pillar 644. Themethod 1200 further includes inserting the first spring end 1004 _(12a)of the twelfth spring 1004 ₁₂ into the second blind hole 822B of thefirst end 818 of the second pillar 624 and inserting the second springend 1004 _(12b) of the twelfth spring 1004 ₁₂ into the fourth blind hole942D of the second end 940 of the fourth pillar 646.

The first embodiment of the present disclosure is illustrated withrespect to FIG. 1 to FIG. 5B, and FIG. 11 . The first embodimentdescribes the flexure bearing 100. The flexure bearing 100 comprisingthe first sleeve 110 and the second sleeve 120, wherein each sleeve 140includes the first pillar 114, 124 having three sides, wherein the firstend 218, 318 of the first pillar 114, 124 is attached to an inside wallof the sleeve 140, and the second end 220, 320 of the first pillar 114,124 projects outwardly from the sleeve 140 parallel to the axis ‘L1’,‘L2’ of the sleeve 140; and the second pillar 116, 126 having threesides, wherein the first end 238, 338 of the second pillar 116, 126 isattached to the inside wall of the sleeve 140, and the second end 240,340 of the second pillar 116, 126 projects outwardly from the sleeve 140such that the second pillar 116, 126 is parallel to and diametricallyopposed to the first pillar 114, 124; the flexure bearing 100 comprisinga plurality of blind holes 150, each blind hole 150 near each of thefirst end 218, 238, 318, 338 and the second end 220, 240, 320, 340 ofeach pillar 148; and the plurality of compression springs 130, eachcompression spring 130 having a first spring end configured to fit intoone of the blind holes 150 of a pillar 148 of the first sleeve 110 and asecond spring end configured to fit into a corresponding blind hole 150of an adjacent pillar 148 of the second sleeve 120 when the secondsleeve 120 is interconnected to the first sleeve 110.

In the flexure bearing 100, the first side 212, 232, 312, 332 of eachpillar 148 is shaped to conform to the sector of the inner surface 206,306 of the sleeve 140, the second side 214, 234, 314, 334 of each pillar148 has the first flat surface 214S, 234S, 314S, 334S, and the thirdside 216, 236, 316, 336 of each pillar 148 has the second flat surface216S, 236S, 316S, 336S perpendicular to the edge of the first flatsurface 214S, 234S, 314S, 334S.

In the flexure bearing 100, each pillar 148 has the first blind hole222A, 242A, 322A, 342A near the first end 218A, 238A, 318A, 338A of thesecond side 214, 234, 314, 334, the second blind hole 222B, 242B, 322B,342B near the first end 218B, 238B, 318B, 33B of the third side 216,236, 316, 336, a third blind hole 222C, 242C, 322C, 342C near the secondend 220A, 240A, 320A, 340A of the second side 214, 234, 314, 334 and thefourth blind hole 222D, 242D, 322D, 342D near the second end 220B, 240B,320B, 340B of the third side 216, 236, 316, 336.

The flexure bearing 100 further comprises the first end cap 402configured to hold the first spring end and the second end cap 402configured to hold the second spring end.

In the flexure bearing 100, the diameter of each end cap 402 is equal tothe diameter of the blind hole 150 and the length of each end cap 402 isequal to the depth of the blind hole 150. In the flexure bearing 100,each compression spring 130 is a helical compression spring.

In the flexure bearing 100, each compression spring 130 has the lengthat least three times of the depth of the blind hole 150.

The second embodiment of the present disclosure is illustrated withrespect to FIG. 6 to FIG. 10 . The second embodiment describes thedouble-ended flexure bearing 600. The double-ended flexure bearing 600comprises the first outer sleeve 610 including the first pillar 614which projects outwardly from the first outer sleeve 610 in the firstdirection ‘D1’; the second outer sleeve 620 including the second pillar624 which projects outwardly from the second outer sleeve 620 in thesecond direction ‘D2’; the central rotor ring 642 having the axis ‘LA3’concentric with the first outer sleeve 610 and the second outer sleeve620, the central rotor ring 642 configured to engage with and connect tothe first outer sleeve 610 and the second outer sleeve 620 along theaxis ‘LA3’, the central rotor ring 642 including the third pillar 644which projects outwardly from the central rotor ring 642 in the firstdirection ‘D1’ and in the second direction ‘D2’; the fourth pillar 646which projects outwardly from the central rotor ring 642 in the firstdirection ‘D1’ and in the second direction ‘D2’; the plurality of blindholes 650 in each pillar 648; and the plurality of compression springs630 configured to connect each of the plurality of blind holes 650 ofeach pillar 648 to the blind hole 650 of the adjacent pillar 648, suchthat the first outer sleeve 610 abuts the first edge 652 of the centralrotor ring 642 and the second outer sleeve 620 abuts the second edge 654of the central rotor ring 642.

In the double-ended flexure bearing 600, each pillar 648 has threesides, including the first side 712, 812, 912, 932 shaped to conform tothe inside wall of one of the first outer sleeve 610, the second outersleeve 620 and the central rotor ring 642; the second side 714, 814,914, 934 having the first flat surface 714S, 814S, 914S, 934S; the thirdside 716, 816, 916, 936 having the second flat surface 716S, 816S, 916S,936S perpendicular to the edge of the first flat surface 714S, 814S,914S, 934S; the first end 718, 818, 918, 938; the second end 720, 820,920, 940; and the center 714C, 716C, 814C, 816C, 914C, 916C, 934C, 936C.

In the double-ended flexure bearing 600, the first end 718C of the firstside 712 of the first pillar 614 is attached to the first inside wall ofthe first outer sleeve 620; the first end 818C of the first side 812 ofthe second pillar 624 is attached to the second inside wall of thesecond outer sleeve 620; the center 912C of the first side 912 of thethird pillar 644 is attached to the first sector of the third insidewall of the central rotor ring 642; and the center 932C of the firstside 932 of the fourth pillar 646 is attached to the second sector ofthe third inside wall of the central rotor ring 642, wherein the firstsector is diametrically opposed to the second sector. In thedouble-ended flexure bearing 600, each pillar 648 has the first blindhole 722A, 822A, 922A, 942A near the first end 718A, 818A, 918A, 938A ofthe second side 714, 814, 914, 934, the second blind hole 722B, 822B,922B, 942B near the first end 718B, 818B, 918B, 938B of the third side716, 816, 916, 936, the third blind hole 722C, 822C, 922C, 942C near thesecond end 720A, 820A, 920A, 940A of the second side 714, 814, 914, 934,the fourth blind hole 722D, 822D, 922D, 942D near the second end 720B,820B, 920B, 940B of the third side 716, 816, 916, 936, the fifth blindhole 722E, 822E, 922E, 942E at the center 714C, 814C, 914C, 934C of thesecond side 714, 814, 914, 934 and the sixth blind hole 722F, 822F,922F, 942F at the center 716C, 816C, 916C, 936C of the third side 716,816, 916, 936.

In the double-ended flexure bearing 600, each compression spring 630 hasthe first spring end configured to fit into one of the blind holes 650of one of the pillars 648, and the second spring end configured to fitinto the corresponding blind hole 650 of the adjacent pillar 648 whenthe first and second outer sleeves 610, 620 are interconnected to thecentral rotor ring 642. In the double-ended flexure bearing 600, thefirst side 712 of the first pillar 614 is shaped to conform to the firstsector of the inner surface 706 of the first outer sleeve 610; thesecond side 714 of the first pillar 614 has the first flat surface 714S;the third side 716 of the first pillar 614 has the second flat surface716S perpendicular to the edge of the first flat surface 714S; the firstside 812 of the second pillar 624 is shaped to conform to the secondsector of the inner surface 806 of the second outer sleeve 620; thesecond side 814 of the second pillar 624 has the third flat surface814S; the third side 816 of the second pillar 624 has the fourth flatsurface 816S perpendicular to the edge of the third flat surface 814S;the first side 912 of the third pillar 644 is shaped to conform to thethird sector of the inner surface 906 of the central rotor ring 642, thesecond side 914 of the third pillar 644 has the fifth flat surface 914S,the third side 916 of the third pillar 624 has the sixth flat surface916S perpendicular to the edge of the fifth flat surface 914S; the firstside 932 of the fourth pillar 646 is shaped to conform to the fourthsector of the inner surface 906 of the central rotor ring 642, thesecond side 934 of the fourth pillar 646 has the seventh flat surface934S, the third side 936 of the fourth pillar 646 has the eighth flatsurface 936S perpendicular to the edge of the seventh flat surface 934S;and wherein each pillar 648 has the first blind hole 722A, 822A, 922A,942A near the first end 718A, 818A, 918A, 938A of the second side 714,814, 914, 934, the second blind hole 722B, 822B, 922B, 942B near thefirst end 718B, 818B, 918B, 938B of the third side 716, 816, 916, 936,the third blind hole 722C, 822C, 922C, 942C near the second end 720A,820A, 920A, 940A of the second side 714, 814, 914, 934, the fourth blindhole 722D, 822D, 922D, 942D near the second end 720B, 820B, 920B, 940Bof the third side 716, 816, 916, 936, the fifth blind hole 722E, 822E,922E, 942E at the center 714C, 814C, 914C, 934C of the second side 714,814, 914, 934 and the sixth blind hole 722F, 822F, 922F, 942F at thecenter 716C, 816C, 916C, 936C of the third side 716, 816, 916, 936.

The third embodiment of the present disclosure is illustrated withrespect to FIG. 1 to FIG. 12 . The third embodiment describes the method1200 of assembling the flexure bearing 100 and the double-ended flexurebearing 600. The method 1200 comprises inserting each first spring endof each compression spring 130, 630 of the plurality of compressionsprings 130, 630 into the blind hole 150, 650 of the pillar 148, 648attached to the first sleeve 110, 610; and inserting each second springend of each compression spring 130, 630 into the corresponding blindhole 150, 650 of the adjacent pillar attached to one of the secondsleeve 120 and the central rotor ring 642.

The method 1200 further comprises inserting the first pillar 114 and thesecond pillar 116 of the first sleeve 110 between the third pillar 124and the fourth pillar 126 of the second sleeve 120; abutting the firstsleeve 110 against the second sleeve 120; and inserting each secondspring end of each compression spring 130 into the corresponding blindhole 150 of the adjacent pillar 148 attached to the second sleeve 120.

The method 1200 of inserting each first spring end and each secondspring end of the plurality of compression springs 130 includesinserting the first spring end 404 _(1a) of the first spring 404 ₁ intothe first blind hole 222A of the first end 218 of the first pillar 114;inserting the second spring end 404 _(1b) of the first spring 404 ₁ intothe third blind hole 342C of the second end 340 of the fourth pillar126; inserting the first spring end 404 _(2a) of the second spring 404 ₂into the first blind hole 242A of the first end 238 of the second pillar116; inserting the second spring end 404 ₂ b of the second spring 404 ₂into the fourth blind hole 322D of the second end 320 of the thirdpillar 124; inserting the first spring end 404 _(3a) of the third spring404 ₃ into the third blind hole 222C of the second end 220 of the firstpillar 114; inserting the second spring end 404 _(3b) of the thirdspring 404 ₃ into the first blind hole 342A of the first end 338 of thefourth pillar 126;

inserting the first spring end 404 _(4a) of the fourth spring 404 ₄ intothe third blind hole 242C of the second end 240 of the second pillar116; inserting the second spring end 404 _(4b) of the fourth spring 404₄ into the second blind hole 322B of the first end 318 of the thirdpillar 124; inserting the first spring end 404 _(5a) of the fifth spring404 ₅ into the second blind hole 222B of the first end 218 of the firstpillar 114; inserting the second spring end 404 _(5b) of the fifthspring 404 ₅ into the third blind hole 322C of the second end 320 of thethird pillar 124; inserting the first spring end 404 _(6a) of the sixthspring 404 ₆ into the second blind hole 242B of the first end 238 of thesecond pillar 116; inserting the second spring end 404 _(6b) of thesixth spring 404 ₆ into the fourth blind hole 342D of the second end 340of the fourth pillar 126; inserting the first spring end 404 _(7a) ofthe seventh spring 404 ₇ into the fourth blind hole 222D of the secondend 220 of the first pillar 114; inserting the second spring end 404_(7b) of the seventh spring 404 ₇ into the first blind hole 322A of thefirst end 318 of the third pillar 124; inserting the first spring end404 _(8a) of the eighth spring 404 ₈ into the fourth blind hole 242D ofthe second end 240 of the second pillar 116; and inserting the secondspring end 404 _(8b) of the eighth spring 404 ₈ into the second blindhole 342B of the first end 338 of the fourth pillar 126.

The method 1200 further comprises inserting the first pillar 614 of thefirst sleeve 610 between the third pillar 644 and the fourth pillar 646of the central rotor ring 642 until the first sleeve 610 abuts the firstedge 652 of the central rotor ring 642; inserting the second pillar 624of the second sleeve 620 between the third pillar 644 and the fourthpillar 646 of the central rotor ring 642 until the second sleeve 620abuts the second edge 654 of the central rotor ring 642; inserting thefirst spring end of each of the plurality of compression springs 630into one of plurality of blind holes 650; and inserting each secondspring end of each compression spring 630 of the first set of theplurality of compression springs 630 into the corresponding blind hole650 of the adjacent pillar 648, wherein the adjacent pillar 648 isattached to one of the first sleeve 610 and the second sleeve 620; andinserting each second spring end of each compression spring 630 of thesecond set of the plurality of compression springs into thecorresponding blind hole 650 of the adjacent pillar 648 attached to thecentral rotor ring 642. The method 1200 of inserting each first springend and each second spring end of the first set of the plurality ofcompression springs 630 includes inserting the first spring end 1004_(1a) of the first spring 1004 ₁ into the first blind hole 722A near thefirst end 718 of the first pillar 614; inserting the first spring end1004 _(2a) of the second spring 1004 ₂ into the second blind hole 722Bnear the first end 718 of the first pillar 614; inserting the secondspring end 1004 _(1b) of the first spring 1004 ₁ into the second blindhole 922B near the first end 918 of the third pillar 644;

inserting the second spring end 1004 _(2b) of the second spring 1004 ₂into the first blind hole 942A near the first end 938 of the fourthpillar 646; inserting the first spring end 1004 _(3a) of the thirdspring 1004 ₃ into the third blind hole 722C near the second end 720 ofthe first pillar 614;

inserting the first spring end 1004 _(4a) of the fourth spring 1004 ₄into the fourth blind hole 722D near the second end 720 of the firstpillar 614; inserting the second spring end 1004 _(3b) of the thirdspring 1004 ₃ into the fourth blind hole 922D near the second end 920 ofthe third pillar 644; inserting the second spring end 1004 _(4b) of thefourth spring 1004 ₄ into the third blind hole 942C near the second end940 of the fourth pillar 646; inserting the first spring end 1004 _(5a)of the fifth spring 1004 ₅ into the fifth blind hole 722E at the center714C of the second side 714 of the first pillar 614; inserting thesecond spring end 1004 _(5b) of the fifth spring 1004 ₅ into the sixthblind hole 922F at the center 916C of the third side 916 of the thirdpillar 646; inserting the first spring end 1004 _(6a) of the sixthspring 1004 ₆ into the sixth blind hole 722F at the center 716C of thethird side 716 of the first pillar 614; inserting the second spring end1004 _(6b) of the sixth spring 1004 ₆ into the fifth blind hole 942E atthe center 934C of the second side 934 of the fourth pillar 646;inserting the first spring end 1004 _(7a) of the seventh spring 1004 ₇into the fifth blind hole 822E at the center 814C of the second side 814of the second pillar 624; inserting the second spring end 1004 _(7b) ofthe seventh spring 1004 ₇ into the fifth blind hole 922E at the center914C of the second side 914 of the third pillar 644; inserting the firstspring end 1004 _(8a) of the eighth spring 1004 ₈ into the sixth blindhole 822F at the center 816C of the third side 816 of the second pillar624; and inserting the second spring end 1004 _(8b) of the eighth spring1004 ₈ into the sixth blind hole 942F at the center 936C of the thirdside 936 of the fourth pillar 646.

The method of inserting each first spring end and each second spring endof the second set of the plurality of compression springs 630 includesinserting the first spring end 1004 _(9a) of the nineth spring 1004 ₉into the third blind hole 822C of the second end 820 of the secondpillar 624; inserting the first spring end 1004 _(10a) of the tenthspring 1004 ₁₀ into the fourth blind hole 822D of the second end 820 ofthe second pillar 624; inserting the first spring end 1004 _(11a) of theeleventh spring 1004 ₁₁ into the first blind hole 822A of the first end818 of the second pillar 624; inserting the first spring end 1004 _(12a)of the twelfth spring 1004 ₁₂ into the second blind hole 822B of thefirst end 818 of the second pillar 624; inserting the second spring end1004 _(9b) of the nineth spring 1004 ₉ into the first blind hole 922A ofthe first end 918 of the third pillar 646; inserting the second springend 1004 _(10b) of the tenth spring 1004 ₁₀ into the second blind hole942B of the first end 938 of the fourth pillar 646; inserting the secondspring end 1004 _(11b) of the eleventh spring 1004 ₁₁ into the thirdblind hole 922C of the second end 920 of the third pillar 644; andinserting the second spring end 1004 _(12b) of the twelfth spring 1004₁₂ into the fourth blind hole 942D of the second end 940 of the fourthpillar 646.

The method 1200 further comprising compressing each compression spring130, 630 before inserting each second spring end of each compressionspring 130, 630 into the corresponding blind hole 150, 650 of theadjacent pillar 148, 648.

Obviously, numerous modifications and variations of the presentdisclosure are possible in light of the above teachings. It is thereforeto be understood that within the scope of the appended claims, theinvention may be practiced otherwise than as specifically describedherein.

1-7. (canceled)
 8. A double-ended flexure bearing, comprising: a firstouter sleeve including a first pillar which projects outwardly from thefirst outer sleeve in a first direction; a second outer sleeve includinga second pillar which projects outwardly from the second outer sleeve ina second direction; a central rotor ring having an axis concentric withthe first outer sleeve and the second outer sleeve, the central rotorring configured to engage with and connect to the first outer sleeve andthe second outer sleeve along the axis, the central rotor ringincluding: a third pillar which projects outwardly from the centralrotor ring in the first direction and in the second direction; a fourthpillar which projects outwardly from the central rotor ring in the firstdirection and in the second direction; a plurality of blind holes ineach pillar; and a plurality of compression springs configured toconnect each of the plurality of blind holes of each pillar to a blindhole of an adjacent pillar, such that the first outer sleeve abuts afirst edge of the central rotor ring and the second outer sleeve abuts asecond edge of the central rotor ring.
 9. The double-ended flexurebearing of claim 8, wherein each pillar has three sides, including: afirst side shaped to conform to an inside wall of one of the first outersleeve, the second outer sleeve and the central rotor ring; a secondside having a first flat surface; a third side having a second flatsurface perpendicular to an edge of the first flat surface; a first end;a second end; and a center.
 10. The double-ended flexure bearing ofclaim 9, wherein: a first end of the first side of the first pillar isattached to a first inside wall of the first outer sleeve; a first endof the first side of the second pillar is attached to a second insidewall of the second outer sleeve; a center of the first side of the thirdpillar is attached to a first sector of a third inside wall of thecentral rotor ring; and a center of the first side of the fourth pillaris attached to a second sector of the third inside wall of the centralrotor ring, wherein the first sector is diametrically opposed to thesecond sector.
 11. The double-ended flexure bearing of claim 10, whereineach pillar has a first blind hole near a first end of the second side,a second blind hole near a first end of the third side, a third blindhole near a second end of the second side, a fourth blind hole near asecond end of the third side, a fifth blind hole at a center of thesecond side and a sixth blind hole at a center of the third side. 12.The double-ended flexure bearing of claim 11, wherein each compressionspring has a first spring end configured to fit into one of the blindholes of one of the pillars, and a second spring end configured to fitinto a corresponding blind hole of an adjacent pillar when the first andsecond outer sleeves are interconnected to the central rotor ring. 13.The double-ended flexure bearing of claim 8, wherein: a first side ofthe first pillar is shaped to conform to a first sector of an innersurface of the first outer sleeve; a second side of the first pillar hasa first flat surface; a third side of the first pillar has a second flatsurface perpendicular to an edge of the first flat surface; a first sideof the second pillar is shaped to conform to a second sector of an innersurface of the second outer sleeve; a second side of the second pillarhas a third flat surface; a third side of the second pillar has a fourthflat surface perpendicular to an edge of the third flat surface; a firstside of the third pillar is shaped to conform to a third sector of aninner surface of the central rotor ring, a second side of the thirdpillar has a fifth flat surface, a third side of the third pillar has asixth flat surface perpendicular to an edge of the fifth flat surface; afirst side of the fourth pillar is shaped to conform to a fourth sectorof the inner surface of the central rotor ring, a second side of thefourth pillar has a seventh flat surface, a third side of the fourthpillar has an eighth flat surface perpendicular to an edge of theseventh flat surface; and wherein each pillar has a first blind holenear a first end of the second side, a second blind hole near a firstend of the third side, a third blind hole near a second end of thesecond side, a fourth blind hole near a second end of the third side, afifth blind hole at a center of the second side and a sixth blind holeat a center of the third side. 14-20. (canceled)
 21. The double-endedflexure bearing of claim 8, wherein each sleeve includes an inside wallhaving a cylindrical inner surface.
 22. The double-ended flexure bearingof claim 21, wherein each pillar comprises a first side shaped toconform to a sector of the inner surface of the other of the first andsecond sleeves, a second side having a first flat surface, and a thirdside having a second flat surface perpendicular to an edge of the firstflat surface.
 23. The double-ended flexure bearing of claim 22, whereineach pillar has a first blind hole near a first end of the second side,a second blind hole near a first end of the third side, a third blindhole near a second end of the second side and a fourth blind hole near asecond end of the third sides.
 24. The double-ended flexure bearing ofclaim 23, wherein the first and second pillars of each sleeve arereceived by the inner surface between the first and second pillars ofthe other sleeve such that the sleeves are rotatably interconnectedabout the sleeve axis.